I could use some advice on my Liliana deck...it generally works, but it's proven to be very slow (largely from the lack of Diregraf and Prized, I assume). I also find that I'm often either fighting for creature space, or suffering from lack of them (I think I need more drawing power).

Current deck is...

Creatures (3)
Undead Servant
Relentless Dead
Voracious Null

Spells (4)
Ever After
Dark Petition
Unholy Hunger
Shamble Back

Support (3)
Shadows of the Past
Sunken Hollow
True-Faith Censer

I added the Censer to try to get the Relentless to die more, in the hopes of pumping Voracious. Unfortunately, that doesn't seem to actually come about that frequently. I'm more tempted to drop the Voracious and forget any hopes of it pumping up (which I don't think I've ever really had happen, or not well at least) in favor of that creature spot for tokens (from Shamble and Undead Servant). Or just giving up on anything really zombie-related until I get Diregraf...

Creatures:Prized Amalgam: discard it. Then bring it back free with floorboard or Colossus. Be warned this guy can freeze the game.Diregraf Colossus: your primary offense/defensive creature. It also brings back Amalgams to bump itself up.

Support:Drownyard Temple: Discard with lily's first ability or behold the beyond to cast it for free with landfall.Corrupted Grafstone: 2 extra black gems every turn.Demonic Pact: ideally you want to cast this when it comes up with behold the beyond to reduce its cost. helps with card draw and discard opponent. can be replace with another removal if you feel it too expansive to cast.

This build leaves the AI empty handed while you beat it up with your zombies. I tried the Relentless Dead and Fleshbag combo. I find that the AI don't have any creature in play for me to remove due to all the discard (most of the time). Plus if anything does get out it well be removed from to the slaughter or die by running in to the colossus.

I could use some advice on my Liliana deck...it generally works, but it's proven to be very slow (largely from the lack of Diregraf and Prized, I assume). I also find that I'm often either fighting for creature space, or suffering from lack of them (I think I need more drawing power).

Current deck is...

Creatures (3)
Undead Servant
Relentless Dead
Voracious Null

Spells (4)
Ever After
Dark Petition
Unholy Hunger
Shamble Back

Support (3)
Shadows of the Past
Sunken Hollow
True-Faith Censer

I added the Censer to try to get the Relentless to die more, in the hopes of pumping Voracious. Unfortunately, that doesn't seem to actually come about that frequently. I'm more tempted to drop the Voracious and forget any hopes of it pumping up (which I don't think I've ever really had happen, or not well at least) in favor of that creature spot for tokens (from Shamble and Undead Servant). Or just giving up on anything really zombie-related until I get Diregraf...

Have other rares that may or may not be applicable/useful, but most probably aren't directly.

Any help/advice would be appreciated.

Considering you're using Liliana with 3 creatures only, I'm not sure you need Dark Petition. You can probably drop that for Ayli, Eternal Pilgrim. Her ability will feed off Relentless Dead rather nicely. Also Baloth Null is counterproductive to your deck as you want your creatures in your graveyard and not in hand. I recommend swapping it for Returned Centaur instead if you have that. Otherwise Read the Bones or some other cheap draw option to draw into your other cards. Just a note that Alhammarret's Archive is too expensive for Liliana to use effectively without having to add more mana ramp cards so it's not a viable option.

And yes you seem to be lacking good cards to build up a faster zombie deck. You've already identified the ones you need, plus Kalitas should you draw into that. Also I would recommend adding in one more creature removal like Grip of Desolation (I see you don't have Unholy Hunger or To the Slaughter) and drop Shadows of the Past. While it's nice to gain life, 12 mana is really expensive for Liliana and more creature removal will likely save you more life than Shadows can potentially gain for you.

With this build, chances are you will be using loyalty more for Liliana's first ability to discard the opponent's cards at the right time or use the second ability to dish out more damage.

Liliana is one of my main decks that I love to use. If we had deck slots I would keep one as vampires and the other as zombies. The below is my vampire build. I would love to hear any advice on this build and how to improve it. I lack quite a few good black cards including the cheap removal cards. That being said I would still love to hear all of your thoughts.

Creatures
Olivia, Mobilized for War: This is the heavy hitter of the deck, if you can get her out you can turn the tides even if you are on death doorstep.
Drana's chosen: Summon zombies to hold down the fort for Olivia or just create a giant zombie mob.
Drana. Liberator of Malakir: Beef up everything quickly
Mindwrack Demon: Quick and powerful summon, plus discards for Liliana's 3rd ability. Hits you for health but usually will beat down your enemy before you die.

Spells
Throttle: I lack good black removal so this is a way to remove little creatures
Grotesque Mutation: Use on Drana, Drana's Chosen or Mindwrack Demon to counteract the demon hitting you for 4 every turn.

Supports
Mirrorpool: Make your creatures big on the cheap.
Corrupted Grafstone: Mana production
Call the Bloodline: bring in little lifegain vampires to help out in a pinch
Retreat to Hagra: Boost your creature on landfall while hitting your opponent and gaining a life.

I would love to hear suggestions on how to make this deck even better. Thank you for any advice you provide.

Choked Estuary(U) - generating mana for you. Be careful as lockdown takes priotity over mana, so only play if against someone how doesn't take big advantage on Blue/Black mana or if your board control is already pretty solid.

The purpose behind the deck is locking down the opponents hand making him discard while ensuring you have enough recyclable Sanitarium Skeleton in hand while controling board with your removal.

The biggest issue you might have would be Creeping Dread wrecking your game by destroying your draw, so make sure to only play it when you've got at least something to ensure you don't empty your hand too much.

If you're already confident on your discard ability you can start moving on to saving for you for your Ability#2: Grave Mist to speed up damage or getting rid of small pestering thing your opponent might summon with his PW Ability (looking at you Gideon#2 and Garruk) or getting overwhelming board control with your Ability#3:Raise Dead, as by this time you've surelly killed Accursed Witch once or twice or even maybe a Fathom Feeder.

Don't mind this 2-month-playing-noob if I said something terribly nonsensical, but here's my contribution.
Lastly thank you Upstartes for the idea.

Spells (6):
Transgress the Mind
Whispers of Emrakul
Grip of Desolation
To the Slaughter
Anguished Unmaking
Behold the Beyond

Supports (2):
Shrine of the Forsaken Gods
Drownyard Temple

Did you ask ME if you could play that creature? No? Can't have it then.
Did you ask ME if you could play that support? No? Can't have it then.
Did you ask ME if you could draw more cards? No? Can't have them.
Did you just take some of MY life total without asking? I'll just get that back now.
Naughty Planeswalker.

*Currently not owned. The idea is to utilise the cards that create supports and if they do get destroyed my Trafficker will pump, they will take damage from Master and/or Herald can weaken their creature.

Journal will repeatedly trigger these with the Clues it spawns and if they destroy it via matches or spells/abilities it will provide these benefits one last time. It's one card I must have. I generally wait on being able to use Liliana' s third ability which can be disastrous if my last three to be destroyed were Master and/or Weaponsmith. Petition also can be disastrous if timed right.

Not much to describe.
- Four removal spells (Oath, Slaughter, Path and Unmaking) to control the board
- One superb hand disruption spell (Obliteration)
- Zombies all the way (all creatures, Graf Harvest, Flooboards)

With Lili2's insane mana generation this will only get much better. I am aware I have no mana acceleration though all spells feel so great unless I get super unlucky with a clunky hand I should be fine.

Before you Knock it .... this was put together on a whim to go against Historic Jace's 4th match (won that one), went 4 of 4 in the training grounds, Streak and I was able to win after a Very, Very long match on the 3rd disk 2nd opponent yet I won it with 46Hp remaining of 94.).